Pipe repair tool and related methods

ABSTRACT

A pipe repair tool includes at least two saddles having an actuatable cylinder disposed therebetween and configured to fit within the pipe, the at least two saddles including arcuate surfaces configured to correspond with a circumference of the pipe.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation-in-Part of U.S. patentapplication Ser. No. 12/940,609, entitled “Pipe Repair Tool and RelatedMethods” filed Nov. 5, 2010, which is incorporated by reference hereinin its entirety.

BACKGROUND

1. Field of the Disclosure

Embodiments disclosed herein relate generally to a pipe repair tool usedfor general field repairs. In particular, embodiments disclosed hereinrelate to a pipe repair tool for repairing out-of-round pipe sections.

2. Background Art

Casing, tubing, joints, liners, drill pipe, drill collars, pup joints,and line pipe (collectively referred to as pipe) may be used in the oiland gas industry to retrieve and transport liquid and gas products. Pipejoints, for example, may be positioned in a wellbore to stabilizeformations or transport referenced products. The pipe joints may becoupled in an end-to-end manner by threaded connections, weldedconnections, or other connections known in the art.

During transport of the pipe from the manufacturer's facility to acustomer, the pipe may become damaged due to excessive movement. Inparticular, the pipe ends may be the most susceptible to damage, forexample, indentations in the circumference of the pipe end. Typically,damaged pipe ends may be classified as “rejects” and must be transportedto a certified threading or end prep facility whereby the pipe end iscut-off and machined to satisfy specification requirements. Thus,machining of the pipe ends at a certified facility as indicated isessentially doubled due to the fact that the threading operation wasperformed twice, in addition to product transportation and handling.

Further, certain lower quality pipe may have certain areas along itslength where a circumference of the pipe is “out-of-round,” i.e., thecircumference may have a degree of ovality. Oftentimes, particularly ifthe defect is near a central portion of the pipe and thus cutting offthe out-of-round end cannot be used to remedy this, the entire pipelength may be scrapped.

Accordingly, there exists a need for a tool capable of repairing damagedpipe ends or out-of-round pipe sections to avoid the need for completere-machining of the pipe ends.

SUMMARY OF THE DISCLOSURE

In one aspect, embodiments disclosed herein relate to a pipe repair toolincluding at least two saddles having an actuatable cylinder disposedtherebetween and configured to fit within the pipe, the at least twosaddles including arcuate surfaces configured to correspond with acircumference of the pipe.

In other aspects, embodiments disclosed herein relate to a method ofrepairing pipe, the method including aligning opposing saddles of a piperepair tool within an out-of-round pipe section, wherein theout-of-round pipe section comprises a short axis and a long axissubstantially perpendicular thereto, and wherein the saddles aresubstantially aligned with the short axis of an out-of-round pipecircumference. The method further includes radially expanding thesaddles against an inner wall of the pipe section in a directionsubstantially parallel with the short axis of the out-of-round pipecircumference, wherein the short axis and the long axis of theout-of-round pipe section are substantially equal after radial expansionof the saddles.

Other aspects and advantages of the invention will be apparent from thefollowing description and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A-1C show perspective views of a pipe repair tool for a pipecoupling in accordance with one or more embodiments of the presentdisclosure.

FIGS. 2A-2C show perspective views of a pipe repair tool for a pipe pinend in accordance with one or more embodiments of the presentdisclosure.

FIG. 3A shows an out-of-round pipe section to be repaired in accordancewith one or more embodiments of the present disclosure.

FIG. 3B shows a repaired round pipe section in accordance with one ormore embodiments of the present disclosure.

DETAILED DESCRIPTION

In one aspect, embodiments disclosed herein relate to a pipe repair toolused in general field repairs. In particular, embodiments disclosedherein relate to a pipe repair tool that may be used for de-dentingdamaged pipe ends. Further, embodiments disclosed herein relate to apipe repair tool that may be used to expand out-of-round pipe sections.In general, the pipe repair tool may be used with a number of differentpipe sizes ranging from 2⅜ inches up to 36 inches, and larger.

Referring now to FIGS. 1A-1C, perspective views of a pipe repair tool100 used for repairing a coupling 50 or box type pipe end havinginternal threads 51 in accordance with one or more embodiments of thepresent disclosure are shown. The pipe repair tool 100 includes twosaddles, an upper saddle 102 and a lower saddle 104. As shown, thesaddles 102, 104 are configured in a semi-circle shape havingarcuate-shaped outer surfaces 103, 105, respectively, which areconfigured to correspond to a circumference of an inner surface 51 of apipe coupling 50. Stated otherwise, the outer arcuate surfaces 103, 105of upper and lower saddles 102, 104 may be configured to be concentricwith the circumference of the inner surface 51 of the coupling 50. Theupper and lower saddles 102, 104 may be configured having a radialthickness (measured in the z-direction) dependent upon a wall thicknessof the pipe end to be repaired. In certain embodiments, the radialthickness of the upper and lower saddles 102, 104 may be at least twicethe wall thickness of the pipe end to be repaired.

Further, in certain embodiments, the upper and lower saddles 102, 104may be configured having threaded outer surfaces 103, 105, respectively,which are configured to correspond with a thread profile of the internalthreads 51 of the coupling 50 (FIG. 1A). The threaded outer surfaces103, 105 may be configured to correspond with any number of the variousthread profiles known in the art. In addition, the upper and lowersaddles 102, 104 may be configured having a counterbore profile at anend 109 that is configured to correspond to a counterbore 53 in a distalend of the pipe coupling 50. Those skilled in the art will appreciate anumber of API standard counterbores to which the end 109 of the upperand lower saddles 102, 104 may be matched.

The pipe repair tool 100 further includes an actuatable cylinder 106disposed between the upper and lower saddles 102, 104, and which isconfigured to expand or extend the upper and lower saddles 102, 104 inopposite directions. The actuatable cylinder 106 (FIG. 1B) may besecured between the upper and lower saddles 102, 104 in any number ofways as known to those or ordinary skill in the art. In certainembodiments, the actuatable cylinder 106 may be a hydraulic jack. As anexample, a low-height, single-acting cylinder available from Enerpac®,located in Butler, Wis., may be used as the actuatable cylinder 106.Further, an external power source such as a hydraulic pump, electricpump, manual hand pump, or hydraulic air pump, also available fromEnerpac®, may be used to actuate the hydraulic jack. The actuatablecylinder 106 is disposed between the upper and lower saddles 102, 104such that a piston (not shown) within the actuatable cylinder 106 may beextended and force the upper saddle 102 away from the lower saddle 104.In certain embodiments, the actuatable cylinder 106 may be rated toprovide up to 10,000 psi, or greater. Moreover, in certain embodiments,the actuatable cylinder may be rated up to about 100 tons, or greater.Alternatively, any type of actuatable cylinder known to those skilled inthe art may be used in accordance with embodiments disclosed herein.

The pipe repair tool 100 may further include one or more alignmenttracks 108 that are configured to maintain an alignment between theupper and lower saddles 102, 104 in a radial direction (i.e., in thez-direction). The alignment tracks 108 provide that the upper saddle 102and lower saddle 104 move directly away from and toward each other(i.e., in substantially 180 degree directions) as the actuatablecylinder 106 expands and retracts. The alignment tracks 108 prevent theupper and lower saddles 102, 104 from becoming misaligned and binding.Those skilled in the art will appreciate a number of variousconfigurations of alignment tracks that may be used in accordance withone or more embodiments disclosed herein.

Still further, the upper and lower saddles 102, 104 may includeattachment points 110 where a linkage (not shown) may be connected tosecure the upper and lower saddles 102, 104 together. For example, thelinkage may include, but is not limited to, a flexible linkage such as achain, flexible strap, or other flexible linkages known to those skilledin the art. Further, the pipe repair tool 100 may include an extensionarm 112 that protrudes axially (i.e., in the y-direction) from the piperepair tool 100. As shown, the extension are 112 may be attached to thelower saddle 104, however, alternatively the extension arm 112 may beattached at any convenient location on the pipe repair tool 100. Theextension arm 112 allows the pipe repair tool to be inserted into a pipeup to a greater distance axially into the pipe length, rather thanmerely at the pipe end.

Referring briefly to FIG. 2A, a perspective view of pipe repair tool 200used for repairing a pin end 60 of a pipe having external threads 61 inaccordance with one or more embodiments of the present disclosure isshown. The pipe repair tool 200 includes an upper saddle 202, a lowersaddle 204, and an actuatable cylinder 206 (FIG. 2B) disposedtherebetween. In this embodiment, the outer arcuate surfaces 203, 205 ofthe upper and lower saddles 202, 204, respectively, are smooth (i.e., nothreaded surface) to correspond with the smooth inner surface of the pinend 60 (due to the pin end 60 having external threads 61). In certainembodiments, the outer arcuate surfaces 203, 205 of the upper and lowersaddles 202, 204 may substantially correspond with an innercircumference of the pipe, such that the saddles 202, 204 exert equalpressure about the circumference of the pipe during expansion of thesaddles 202, 204. In alternate embodiments, the outer arcuate surfaces203, 205 may be tapered along lengths thereof such that a diameter ofthe arcuate surfaces increases or decreases along lengths thereof. Thepipe repair tool 200 further includes alignment tracks 208, attachmentpoints 210, and an extension arm 212 similar to the previous embodimentdescribed above.

Referring now to FIGS. 1A-1C and 2A-2C together, methods of using thepipe repair tools 100, 200 in accordance with one or more embodimentsdisclosed herein are as follows. As shown in FIGS. 1A and 2A, often adamaged pipe end 50, 60 will have an indentation 52, 62 that protrudesin a radially inward direction. A damaged pipe end 50, 60 with such anindentation 52, 62 is often classified as a reject and may not be usedunless costly remanufacturing steps are undertaken (i.e., cutting thedamaged end and rethreading). Using a pipe repair tool in accordancewith methods disclosed herein, the damaged pipe end may be repaired suchthat the pipe length may be used.

The pipe end is first inspected to determine whether the pipe end issalvageable and if use of the pipe repair tool may be sufficient torepair the damage to the pipe end. For a damaged pipe coupling 50 (withinternal threads 51), if the indentation area 52 (FIG. 1A) exceeds thefirst two threads axially inward from the coupling end, or if theinternal threads 51 are detected to have encountered any tears, cut,grinds, shoulders, steps, or any other imperfections and/or damage thatbreaks the thread continuity in the indented area, or if any couplingface damage with raised metal is detected, the coupling 50 may likelyremain in the reject category (i.e., the coupling is beyond repair).Likewise, for a damaged pin end 60 (with external threads 61), if theindentation area 62 (FIG. 2A) exceeds the second full crested threadfrom the pin nose face, or if the external threads 61 are detected tohave encountered any tears, cuts, grinds, shoulders, steps, or any otherimperfections and/or damage that breaks the thread continuity in theindented area, or if any pin end damage with raised metal is detected,the pin end 60 may likely remain in the reject category (i.e., the pinend is beyond repair).

Still further, for damaged plain end casing (not shown), if theindentation exceeds API Specification 5CT requirements for outerdiameter (“OD”) dimensional requirements, the damaged plain end casingmay remain in the reject category. Further, for damaged plain end linepipe, if the indentation exceeds API Specification 5L requirements,which state that pipe shall contain no indentations greater than ¼ inch(0.250 inch) measured as the distance between the lowest point of theindentation (i.e., the furthest point radially inward) and aprolongation of the original contour of the pipe, the damaged line pipemay remain in the reject category. If the damaged pipe end is determinedto be repairable, the repairs may be commenced as follows.

To repair the damaged pipe end, the pipe may be rotated until thedamaged area 52 (FIG. 1A) is located at approximately a 12 o'clockposition (i.e., the indentation is on top). Next, the pipe repair tool100 may be inserted into the pipe end as shown in FIG. 1B. The uppersaddle 102 may be aligned with the indentation 52 such that theindentation 52 is positioned in approximately the center of the uppersaddle 102. The lower saddle 104 is configured to engage a lower half ofthe pipe end circumference to provide a stable base during repair. Thelower saddle 104 may be configured to have an arcuate outer surface 105length of up to approximately ½ of the circumference of the pipe end. Ingeneral, the greater the length of the arcuate outer surface 105, thebetter stability the lower saddle 104 is able to provide during repairof the pipe end. Further, during repair of a pipe coupling havinginternal threads, the threaded outer surface 105 of the lower saddle 104is matched to correspond with the internal threads 51 of the pipecoupling 50. The threaded outer surface 105 of the lower saddle 104 ismatched with the internal threads 51 to avoid deforming the internalthreads during repair.

Likewise, referring briefly to FIGS. 2A-2C, to repair a pin end 60 of apipe the pipe repair tool 200 may be inserted into the pin end 60 andoriented such that the upper saddle 202 is approximately centered on theindentation 62. Because the pin end 60 has external threads 61, theupper and lower saddles 202, 204 have outer surfaces 203, 205 that aresmooth and configured to correspond with the smooth inner surface of thepin end 60. Further, in certain embodiments, a shim (not shown) may beinserted between the upper and lower saddles 202, 204 and an innersurface of the pin end 60 to avoid direct contact between the outersurfaces 203, 205 of the upper and lower saddles 202, 204 and the innersurface of the pin end 60. The shim may be relatively thin and isintended to prevent any marring or deforming of the inner surface of thepin end 60.

After the pipe repair tool is properly positioned in the pipe end, theactuatable cylinder may be actuated and a piston within the actuatablecylinder expanded to urge the upper saddle into contact with an innersurface of the damaged section of the pipe end. In the embodiment shownin FIGS. 1A-1C, similar to the lower saddle 104, the upper saddle 102 isconfigured having a threaded outer surface 103 configured to correspondwith the internal threads 51 of the pipe coupling 50. The upper saddle102 is expanded to contact the damaged surface 52. The outward radialforce from the expanding upper saddle 102 forces the indentation 52 ofthe damaged section radially outward and restores the pipe coupling 50to its original outer diameter. Once the damaged section of the pipecoupling 50 reaches the original diameter contour, the pressure to theactuatable cylinder is released to allow the upper saddle 102 to retractaway from the inner surface of the pipe end 50.

Still further, in certain embodiments, prior to relieving pressure inthe actuatable cylinder and retracting the upper saddle, the uppersaddle may remain in contact with the inner surface of the pipe end andthe repaired pipe end may be work-hardened or strain-hardened. Therepaired pipe end may be work-hardened to ensure that the repaired outerdiameter contour is permanent and that the damaged section (i.e., theindentation) does not return to the damaged state whatsoever (i.e., thatthe indentation does not return). Any type of cold-working orwork-hardening process may be used to induce slight permanentdeformation of the metal and exact the shape change (i.e., return thepipe end to its original outer diameter contour). For example,repetitively struck blows from a large hammer on an outer surface of therepaired pipe end may effectively cold-work the pipe end.

Following repairs to the pipe end, an inspection of the repaired pipeend may be conducted to ensure that the repaired pipe end has beenrepaired to proper dimensions and within proper tolerances. A threadelement and/or pipe end dimensional inspection may be performed toensure compliance with respective API Specifications (e.g., APISpecifications 5CT, 5B, 5L and 5A5) in addition to any customerspecification requirements, as will be known and understood by one ofordinary skill in the art. For example, a ring gauge or plug gauge maybe employed to confirm that the repaired pipe end meets APIspecification requirements. Those skilled in the art will understand theuse of a ring or plug gauge to do so.

In other embodiments, the pipe repair tool may be used for cold workedcircumference rounding (“CWCR”) at a particular section of the pipelength having an out-of-round circumference. The pipe repair tool may beused to cold work or return the out-of-round circumference back to asubstantially round circumference. For example, referring to FIGS. 3Aand 3B, cross-section views of an out-of-round pipe circumference (FIG.3A) and round pipe circumference (FIG. 3B) are shown. As shown in FIG.3A, the out-of-round pipe has a more oval circumference with a shortaxis, indicated by “S,” and a long axis, indicated by “L.” In contrast,a round pipe circumference, shown in FIG. 3B, has two substantiallyequal axes, indicated by “E.” In other embodiments, the pipe repair tool100 may be used to cold work a pipe circumference having an indentationat one or more locations around the circumference of the pipe. Forexample, a “flat spot” or other defect or indentation may be cold workedusing the pipe repair tool 100 in accordance with one more embodimentsof the present disclosure.

The pipe repair tool 100, with the saddles 102 retracted, may beinserted into the pipe and positioned at a particular axial locationalong the pipe length to be cold worked (i.e., axially adjacent theout-of-round circumference). The saddles may be rotationally oriented inalignment with or along the short axis “S” as shown. As such, outwardexpansion of the saddles 102 (with actuatable cylinder) in the directionof the short axis “S,” indicated by arrows “1,” against the inner wallof the pipe length may force the walls radially outward, thereby coldworking and returning the pipe circumference to a substantially roundconfiguration shown in FIG. 3B.

To determine an amount of expansion exerted by the saddles, an initialmeasurement using a Pi tape, micrometer, or other known measurementdevices, may be used prior to expansion to establish a baselinemeasurement from which a subsequent post-expansion measurement may becompared. After a first attempt at cold working of the out-of-roundsection, the Pi tape may be used again to record a measurement at thecold worked section. If enough expansion has occurred in the pipecircumference, the operation may cease. Otherwise, additional expansionstrokes of the saddles may be required before the pipe section is backwithin a suitable round configuration. Those skilled in the art willunderstand pipe sections that may be deemed out-of-round according tovarious pipe and conduit standards, including but not limited toAmerican Petroleum Institute (API) standards, American Society forTesting and Materials (ASTM) standards, American Water Works Association(AWWA) standards, and other domestic and foreign standards.

In certain embodiments, the saddles may be expanded a single time beforethe pipe circumference is back within round. In other embodiments,multiple expansions and retractions of the saddles may be required. Incertain embodiments, the pipe circumference may be worked by betweenabout one thousandth and about one hundred thousandths of an inch. Inother embodiments, the pipe circumference may be worked by between aboutone thousandth and about sixty five thousandths of a inch. In stillother embodiments, the pipe circumference may be worked by between aboutfive thousandths and about twenty thousandths of an inch. Finally, instill further embodiments, the pipe circumference may be worked bybetween about ten thousandths and about twelve thousandths of an inch.For example, a high collapse pipe section (e.g., HCP110) having a wallthickness of about 0.472 inches may be cold worked up to about ninetythousandths of an inch in accordance with one or more embodiments of thepresent disclosure.

Advantageously, embodiments of the present disclosure provide a piperepair tool capable of returning a damaged pipe end to originalspecifications as allowed by API specification standards. Particularly,embodiments disclosed herein eliminate the need to cut and rethread thepipe end due to minor repairable damage of the pipe end. Thus, the piperepair tool may save repair costs of damaged pipe ends as well asdecrease the time required to make the repair itself. Further,embodiments disclosed herein provide a pipe repair tool capable of coldworked circumference rounding for out-of-round or flat pipe sections,which return the pipe circumference to a substantially roundcircumference.

While the present disclosure has been described with respect to alimited number of embodiments, those skilled in the art, having benefitof this disclosure, will appreciate that other embodiments may bedevised which do not depart from the scope of the disclosure asdescribed herein. Accordingly, the scope of the disclosure should belimited only by the attached claims.

1. A pipe repair tool comprising: at least two saddles having anactuatable cylinder disposed therebetween and configured to fit withinthe pipe, the at least two saddles comprising arcuate surfacesconfigured to correspond with a circumference of the pipe.
 2. The piperepair tool of claim 1, wherein the actuatable cylinder is configured toexpand the at least two saddles in opposite directions.
 3. The piperepair tool of claim 1, wherein the arcuate surfaces of the at least twosaddles are configured to be substantially concentric with thecircumference of the pipe.
 4. The pipe repair tool of claim 1, whereinan arc length of the arcuate surfaces is approximately one-half or lessof the circumference of the pipe.
 5. The pipe repair tool of claim 1,wherein the actuatable cylinder is a hydraulic cylinder.
 6. The piperepair tool of claim 1, further comprising an external power source influid communication with the actuatable cylinder.
 7. The pipe repairtool of claim 1, further comprising at least one alignment memberconfigured to maintain a radial alignment between the at least twosaddles.
 8. The pipe repair tool of claim 1, wherein a radial thicknessof the at least two saddles is at least twice the wall thickness of thetubular.
 9. The pipe repair tool of claim 1, further comprising at leastone linkage between the at least two saddles.
 10. The pipe repair toolof claim 1, wherein the actuatable cylinder is configured to provide apressure of up to 10,000 psi.
 11. The pipe repair tool of claim 1,wherein a profile of the at least two saddles is configured tocorrespond to a standard counter bore of the pipe.
 12. The pipe repairtool of claim 1, wherein the arcuate surfaces of the at least twosaddles are configured to provide equal pressures around a pipecircumference during expansion.
 13. The pipe repair tool of claim 1,wherein the actuatable cylinder is configured to provide up to about 100tons of force.
 14. A method of repairing pipe, the method comprising:aligning opposing saddles of a pipe repair tool within an out-of-roundpipe section, wherein the out-of-round pipe section comprises a shortaxis and a long axis substantially perpendicular thereto, and whereinthe saddles are substantially aligned with the short axis of anout-of-round pipe circumference; and radially expanding the saddlesagainst an inner wall of the pipe section in a direction substantiallyparallel with the short axis of the out-of-round pipe circumference;wherein the short axis and the long axis of the out-of-round pipesection are substantially equal after radial expansion of the saddles.15. The method of claim 14, further comprising work-hardening thesection of the pipe having the indentation after returning thecircumference of the pipe to the original outer diameter contour. 16.The method of claim 14, further comprising dimensionally inspecting thethreaded pipe.
 17. The method of claim 16, further comprising insertinga shim between an outer surface of the at least two saddles and an innersurface of the out-of-round pipe section.
 18. The method of claim 16,further comprising providing threaded outer surfaces on the at least twosaddles to correspond with an internal thread of the pipe section. 19.The method of claim 16, further comprising providing smooth outersurfaces on the at least two saddles to correspond with a smooth innersurface of the pipe section.
 20. The method of claim 14, furthercomprising repairing the indentation according to API specificationrequirements.